Electric fence testing device utilizing an arc gap



1968 ALT. BERG, JR, ETAL 3,3 4,424

ELECTRIC FENCE TESTING DEVICE UTILIZING AN ARC GAP Filed Nov. 8, 1966 w 6 f w 1 NEW 3 M TA J RW W 50 5H M M w J J M 1/ W fl )WM w 1% W United States Patent I 3,364,424 ELECTRIC FENCE TESTING DEVICE UTILIZING AN ARC GAP Albert T. Berg, Jr., and Howard Langlie, Ellendale,

Minn., assignors to North Central Plastics, Inc, Ellendale, Mirna, a corporation of Minnesota Filed Nov. 8, 1966, Ser. No. 592,902 3 Claims. (Cl. 324-72.5)

ABSTRACT OF THE DISCLOSURE An L-shaped metallic rod has its relatively short leg housed in a dielectric handle composed of two plastic shells that are secured to each other. An apertured plate within the handle mounts a screw for advancement and retraction with respect to the upper end of the relatively long leg of the rod to draw an are when a projecting tongue on the plate is placed in engagement with an elevated wire of an energized electric fence and when the lower end of said relatively long rod is touching the ground. A notch formed in the handle guides the tongue onto the fence wire. The fence wire can be shorted to ground when the screw is advanced in contradistinction to the arc that is drawn when it is retracted.

I his invention relates generally to electric fence testing devices, and pertains more particularly to a device of this type that will enable the user to draw an electric are which signifies that the fence is properly energized or to short out the fence if circumstances so dictate.

Electric fences are widely employed on ranches and farms for confining cattle and the animals rapidly learn to respect the fence. However, the fence must be maintained in an operable condition in order to be efiective. Various troubles can arise which will make an electric fence inoperative and checks or tests of the fence must be made to determine whether it is energized. Also, where a fence is in need of repair, the controller must either be disconnected or the fence grounded in order to short out the controller.

One object of the present invention is to provide a portable fence testing device that will permit the fence to be quickly tested by drawing or establishing an electric are which visually indicates that the fence is in an energized condition.

Another object is to provide a fence tester that is also capable of shorting out the fence so that repair work can be performed on the fence without having to disconnect the controller which might be a considerable distance away. Our testing device additionally obviates the need for resorting to makeshift shorting schemes.

Another object of the invention is to provide a portable fence tester that can be manufactured and sold at a relatively low price, thereby encouraging its widespread use. More specifically, it is recognized that fence testing devices have been in the past devised which utilize a lamp for the purpose of indicating when a fence is energized. However, such devices are more costly to manufacture than the instant device because of the lamp, its mounting and associated wiring.

A further object is to provide a fence testing device that is compact and lightweight, making it easy to carry about so that it is available when needed.

These and other objects and advantages of our invention will more fully appear from the following description, made in connection with the accompany drawing, wherein like reference characters refer to the same or similar parts throughout the several views and in which:

FIGURE 1 is a perspective View of our fence testing device in actual use;

FIGURE 2 is a sectional view taken in the direction of line 2-2 of FIGURE 1, and

FIGURE 3 is a sectional view taken in the direction of line 3-3 of FIGURE 2.

Referring now in detail to the drawing, the elecric fence testing device exemplifying our invention has been designated in its entirety by the reference numeral 10. From FIGURE 2, it will be discerned that the device includes a handle 12 comprised of an upper shell 14 and a lower shell 16. Inasmuch as the handle 12 is to be of an electrically insulating character, the shells 14, 16 are fabricated from suitable dielectric material, such as molded phenolic resin, although other plastic materials can be employed if desired. As can be seen from FIGURE 2, the shells 14 and 16 are molded with a rabbeted or shouldered joint at 18 so as to form the handle 12 when assambled, an appropriate adhesive also normally being used in retaining the shells 14 and 16 in their assembled relationship.

A metallic rod 20 has a vertical leg 22 projecting downwardly and a horizontal leg 24 contained within the interior of the handle 12. It will be noted that the lower shell 16 has an integral tubular portion 26 formed with a pair of opposed ribs 28 and 30, these ribs diverging slightly in an upward direction. Before the shells 14 and 16 are adhered together, the rod 20 can be forced downwardly so that its vertical leg is frictionally retained between the two ribs 28 and 36.

From FIGURES 2 and 3, it will be discerned that the upper shell 14 is internally grooved at 32 and that the lower shell 16 is internally grooved at 34. The grooves 32 and 34 are in vertical registry with each other. The purpose of the grooves 3 2, 34 is to accommodate a metallic insert plate 36. The plate is of such thickness that it can be received in the lower groove 34 and a portion thereof is likewise received in the upper groove 32 when the upper shell 14 is placed on the lower shell 16. The plate 36 is formed with a hole 38 and a downwardly projecting tongue 40. The tongue extends through a rectangular opening or slot 42 in the lower shell 16. More specifically, the tongue 40 projects into a downwardly diverging or flaring notch 44 formed by the body of the shell 16 and a flange or lip 46 integrally molded thereon.

A metallic contact member 48 has a threaded shank 50 and a knurled or serrated section 52. Actually, the contact member 48 is in the form of a self-tapping screw and by reason of the hole 38, the contact member can be mounted so as to be advanced and retracted within the handle 12. It will be recalled that the insert plate 36 is held in place by the grooves 32 and 34. In order to afford a facile means for manipulating the contact member 48, a knob 54 of dielectric material having an axial recess 56 therein has the section 52 of the contact member 48 pressfitted into said recess. The knob 54 extends through an opening 58 in the handle 12 so as to make it accessible to the user.

Since the knob 54 projects outwardly from the handle 12, it can be rotated in opposite directions so as to cause the right end, as viewed in FIGURE 2, of the contact member 48, to engage a portion of the vertical leg 22 of the rod 20. Retraction of the contact member 48 is instrumental in drawing or establishing an electric arc when the fence being tested is properly energized, as will become clearer when considering an operational description of the invention.

To allow viewing of the are when established, a peep hole 60 is provided in the upper shell 14 in vertical alignment with the otherwise concealed locus where the contact member 48 engages the rod 20.

In use, as illustrated in FIGURE 1, our device 10 is placed over a fence wire 62, or if the electric fence is composed of strands of wire over such strands, then the lower end of the rod 20 is force downwardly so as to engage the ground at 64. The fence wire 62, quite obviously, can be deflected sufficiently so as to allow the lower end of the rod 24} to engage the ground 64.

Assuming that the contact member 48 is in the position pictured in FIGURE 2, such a course of action will result in the electric fence being shorted out because of the electrical path from the fence wire 62 through the insert plate 36, through the contact member 4-8 and the rod 26. Under these circumstances, the electric fence can be safely worked upon to make any needed repairs. However, if the fence is to be merely tested as to whether it is in an energized state, the user will then rotate the knob 54 so as to retract or withdraw the contact member 48. Only a slight retraction is needed in order to provide a gap between the contact member 48 and the rod 20. This gap causes an electric arc to be drawn and the peep hole 60 permits the user to ascertain when such are is established. The presence of such an are automatically signifies that the fence is in an operable condition and the test or check is in this way quickly completed.

It will, of course, be understood that various changes may be made in the form, details, arrangements and proportions of the parts without departing from the scope of our invention as set forth in the appended claims.

We claim:

1. An electric fence tester comprising a dielectric handle composed of upper and lower plastic shells bonded together to provide a hollow interior, said lower shell having a rectangular opening and a downwardly facing notch diverging from said opening, an apertured metallic insert plate contained in said handle and having a tongue projecting downwardly through said opening so as to engage the wire of an electric fence when guided thereonto 35 by said notch, a metallic screw threadedly supported by said plate so as to be advanced and retracted relative thereto, and an L-shaped metallic rod having a relatively short horizontal leg contained in said housing and a relatively long vertical leg extending perpendicularly downwardly from said horizontal leg through said lower shell and projecting from said lower shell sufliciently so as to engage the ground when said tongue is engaging said fence wire, said screw being at an elevation slightly lower than said horizontal leg and aligned with the upper end of said vertical leg so as to engage said vertical leg when advanced relative to said plate and thus ground the fence and to establish an electric arc when retracted relative said plate from said vertical leg and said fence is electrically energized, said upper shell having a viewing opening in the top thereof vertically aligned with said vertical leg for affording a visual indication when said arc is established.

2. An electric fence tester in accordance with claim 1 in which said upper and lower shells each has an internal groove for accommodating marginal portions of said plate to retain said plate in a parallel relation with said vertical leg.

3. An electric fence tester in accordance with claim 1 including a dielectric knob fixedly carried on the end of said screw more remote from said vertical leg for manipulating said screw to advance and retract same.

FOREIGN PATENTS 189,574 12/1922 Great Britain. 683,997 12/1952 Great Britain.

RUDGLPH V. ROLTNEC, Primary Examiner.

E. L. STOLARUN, Assistant Examiner. 

